For passenger comfort the centripetal acceleration on a railway curve must not exceed 2 m/s². What is the smallest radius rmin for a curve taken at 240 km/h?
Circular motion worksheet with answers
A small object sits 80 cm from the axis of a disc that turns at a steady 120 revolutions per minute. Find its centripetal acceleration ac.
A car takes a flat curve of radius 20 m. The coefficient of static friction between tyres and road is 0.4. Use g = 9.81 m/s². Find the highest speed vmax at which the car can take the curve without skidding.
A car takes a flat curve of radius 150 m. The coefficient of static friction between tyres and road is 0.8. Use g = 9.81 m/s². Find the highest speed vmax at which the car can take the curve without skidding.
A 1.9 kg ball on a string 1.5 m long is swung in a vertical circle. At the lowest point it moves at 7.5 m/s. Use g = 9.81 m/s². Find the tension T in the string at the lowest point.
A 2 kg cart is released from rest at a height of 11.6 m on a frictionless track and runs through a vertical loop of radius 4 m. Use g = 9.81 m/s². Find the normal force Nbottom of the track on the cart at the bottom of the loop.
Answer key
- 1. rmin = 2222 m
- 2. ac = 126.3 m/s²
- 3. vmax = 8.859 m/s
- 4. vmax = 34.31 m/s
- 5. T = 89.89 N
- 6. Nbottom = 133.4 N
Full step-by-step solutions: practise this topic on examproblems.com.